中文摘要：

基于2006年南极威德尔海冬季科学考察期间由机载激光测高仪测得的海冰上表面高度数据,以脊高和脊距的理论与实测概率密度的相对误差之和为性能指标,以切断高度为控制变量建立优化模型。结果表明,W＇80型分布和对数正态分布分别与实测脊高和脊距分布吻合较好;最优切断高度为0.62 m。进而从海冰表面起伏中确定出冰脊。利用k均值聚类算法以冰脊强度（Ri）为标准将剖面分为3类（Ri≤0.01,0.01〈Ri≤0.026和Ri〉0.026）。对应各类剖面分别有：平均脊高为0.99 m,1.12 m和1.17 m;平均脊距为232 m,54 m和31 m。利用数学模型估算并分析了多脊冰平均厚度、有效厚度,帆横截面积及冰脊所占面积,这些参数值均随冰脊强度增大而增大。

英文摘要：

Based on the surface elevation profiles of sea ice in the Weddell Sea measured by a helicopter-borne laser altimeter during the Winter Weddell Outflow Study 2006,an optimal model is established with the relative deviations between the theoretical and measured ridge height（spacing） distributions as the performance index and the cutoff height as a control variable.An optimal cutoff height of 0.62 m is obtained and used to separate ridges from level ice surface.Analysis on the ridge distributions implies that the best fits to the observed sail height and spacing distributions are achieved by W′80 distribution and a lognormal distribution,respectively.All profiles are clustered into three regimes by the k-means algorithm based on the ridging intensity Ri（Ri ≤0.01,0.01Ri ≤0.026 and Ri0.026）.The average sail height is 0.99m for the profiles of Ri ≤0.01,1.12 m for 0.01Ri ≤0.026,and 1.17 m for Ri0.026.While the average spacing are 232m,54 m and 31 m respectively for the three different regimes.Effective thickness within the area covered by ridged ice,average thickness of ridged ice,sail cross-section,and the areal fraction of ridged ice are also calculated by the mathematical models,and the results indicate that these parameters increase with increase of the ice ridge intensity.